■ : . This bad result was due to the snrae conditions laentioned in 

 earlier reports. Lack of crabs for food - together vdth a growing 

 infection of the lobster youn-g by a few tenths of a rdllimeter long 

 "suctorie". One single young lobster could have a hundred or more 

 of these individuals. . , 



According to a preliiainary determination, made by conservator 

 Dons in Trondheim, it is a "suctorie", Ephe 1 ot a_ j ei.mipar a , which 

 very frequently is to be found in the sea. This is a highly organ- 

 ized one-celled animal* 



TJheth.er the "suctorie" is the real cause of the mortality is, 

 however, not certain. There is a possibility th'vt the mortality is 

 due to bacteria which developed on account of pollution in the salt 

 water reservoir and that the same pollution was the cause of the 

 development of the suctorians. 



YJTrien this is vnritten, August 1927, it appears that both the 

 infection as well as the mortality of the young lobsters stopped 

 when the basin had been thorou,-^hly cleaned. It was also empty during 

 a cold period last fallo 



By thoroughly going tlirough certain lobster material \Te see that 

 it has also appeared in earlier ye^rs, but in a smr.ll number. It 

 also occurs in small quantity this season but v;ithout doing any harm. 



In the absence of sea crabs, mussels and sand crabs were used 

 for food. This is supposed to be. .a, sufficiently nutritive food, but 

 because this can be served only, in a ground (crushed) condition^ so 

 much inedible stuff goos with it that it pollutes the v;ater. Also 

 the meats are so.iewhat heavy, they are apt to sink. Understanding 

 this, we had to find a method to clean the water in the rearing 

 apparatus for food remains. That vrfiich san.k to the bottom v/as sucked 

 up with a .siphon or washed out when the apparatus were cleaned; (the 

 young are transferred to a clean box every day or e^-ery second day). 

 There were more difficulties vdth the floating particles. An earlier 

 accident v;ith the supply of water- gave ne, however, a usable idea. 



The centrifugal pump draws some air. when there is .a lea.kage in 

 the storerooms; this air is v;hipped into thev/ater by the quickly 

 rotating. wheel and the water i-n the suction pipe therefore sparkles 

 like the carbonic- acid in soda v/ater. On one occasion the water from 

 the pump-hose was led directly into the rearing apparatus \Tith the 

 result that both the brood and the food iramedirtely rose to the sur- 

 facee The air bubbles attrchod themselves, to all floating particles, 

 including the lobster youngs 



Wow, by leading an adequate quantity of "sparkling" Wfiter from 

 the piunp-hose to the hose of the apparatus, I succeeded in getting 

 to the surface all small particles, i;hich, could be skimmed off, 

 while the young lobsters were not affected at. all. In tliis way all 



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